Equivalency of the Casimir and the Landau-Lifshitz approaches to continuous-media electrodynamics and optical activity on reflection

The controversial discussion on the existence of the specular optical activity phenomenon is reexamined. We prove here that the effect is predicted by approaches based both on the Casimir and the Landau-Lifshitz material equations and that these equations are in fact equivalent if crucial terms containing the derivatives of the nonlocal susceptibilities are taken into account in the derivation. Polarization azimuth rotation in the reflected wave of the scale 2×${10}^{\mathrm{-}6}$–2×${10}^{\mathrm{-}4}$ rad may be expected in absorbing optically active crystals. We also show that specular optical activity is intrinsically linked with the transmission effect.